Exchange 2013 CU5 upgrade fails with error – The object already exists

Just ran into this one,

An existing Exchange 2013 CU2 installation was requested to be updated to CU5, nothing special there…

Once trying to run the CU5 setup.exe /PrepareAD , the setup failed with an error:
[02/07/2014 11:57:49.0192] [1] [ERROR] Active Directory operation failed on dc.domain.com. The object 'CN=Default,CN=OWA Mailbox Policies,CN=Exchange,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=domain,DC=com' already exists.
[02/07/2014 11:57:49.0192] [1] [ERROR] The object exists.

Digging in the ExchangeSetup.log file, I’ve tried to identify the cause.

[02/07/2014 11:57:49.0192] [1] [ERROR] The following error was generated when "$error.Clear();
$policyDefault = Get-OwaMailboxPolicy -DomainController $RoleDomainController | where {$_.Identity -eq "Default"};

if($policyDefault -eq $null)
{
New-OwaMailboxPolicy -Name "Default" -DomainController $RoleDomainController
}
" was run:
"Microsoft.Exchange.Data.Directory.ADObjectAlreadyExistsException:
Active Directory operation failed on dc.domain.com. The object 'CN=Default,CN=OWA Mailbox Policies,CN=Exchange,CN=Microsoft
Exchange,CN=Services,CN=Configuration,DC=domain,DC=com' already exists. ---> System.DirectoryServices.Protocols.DirectoryOperationException:
The object exists.

So I’ve tried to reproduce the test manually using the same command in the setup:
Get-OwaMailboxPolicy -DomainController $RoleDomainController | where {$_.Identity -eq "Default"}
And the result was indeed $null .. which made no sense here… because it does exists, as the error states – the object ‘CN=Default,CN=OWA Mailbox Policies,CN=Exchange,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=domain,DC=com’ already exists.

Then I’ve noticed that the CN was “default” with lower “d” … although the Where-Object and -eq should be case insensitive, the check failed…

So, I’ve modified the value to be “Default” with capital “D”:

Set-OwaMailboxPolicy -Identity default -Name Default

that did the trick 🙂 and the setup.exe /PrepareAD was successful.

ilantz